Pulverized-fuel burner



Nov. 26, 1929. 0. DE LORENZ! PULVERIZED FUEL BURNER 2 Sheets-Sheet FiledSept. 50 1926 Qttomm a Y Z N V- 6, 1929- 0. DE LORENZ] PULVERIZED FUELBURNER Filed Sept. 30 1926 2 Sheets-Sheet Patented Nov. 26,1929

UNITED STATES PATENT OFFICE OTTO D2 LORENZI, OF MAPLEWOOD, NEW JERSEY,ASSIGNOR TO INTERNATIONAL COMBUSTION ENGINEERING CORPORATION, OF NEWYORK, N. Y., A CORPORATION OF DELAWARE PULVERIZED-FUEL BURNERApplication filed September so, 1926. Serial No. 138,597.

This invention relates to burners for pulverized fuel and has particularreference to burners in which the fuel is delivered to the burner nozzlewit-h substantially no more air than is necessary for carrying purposes,the remainder of the air necessary for' combustion being admitted,preferably, at or in the immediate vicinity of the burner nozzle.

. The primary object of the invention is to provide an effective controlof air admitted at the burner for various rates-of firing'and to sodispose the air and fuel inlets into the furnace that thorough admixtureand efficient combustion will result at Widely varying rates of firing.

I have illustrated my invention, in preferred embodiment, in theaccompanying drawings wherein:

Figure 1 is a section through my improved burner taken on theline 1-1 ofFigure 2;

Figure 2 is a front elevation of the burner;

Figure 3 is a section of a modification of my invention;

Figure 4 is a rear elevation of the burner nozzle and fuel supply line;and,

Figures 5 and 6 are developed views illustrating closed and openpositions, respectively, of the air admission fins of the burner shownin Figure 3. j

Referring now to Figures 1 and 2 it will be seen that the burnercomprises a cylindrical casing 7 shown as having two tangential airsupply connections 8, although only one may be used if desired. Aflanged ring 9 is embedded or bricked in the. furnace wall and assistsin supporting the casing 7. The burner nozzle 10 comprises twosubstantially truncated conical members ll an d 12, each having a flange13 around the-periphery of its flaring end, which are bolted togetherwith the edge 14 of an opening in the back 15 of the. casing 7. Themember 12 has a fuel supply pipe 16 discharging tangentially thereintoadjacent the truncated end. A clean-out plate 17 provided with anobserva tion glass 18 is bolted to the back of the member .12. i e VAnother truncated conical member 19 having air admissionopenings 20 issupported in the burner casing, at the front by the ring 21 and at therear by the flange 22 bolted to a cylindrical seat 23 formed on thenozzle member 11 near its delivery opening 24. Air openings 25 are alsoprovided in the shoulder 26 of the conical member 19 adjacent thedelivery end of the nozzle 10. A frusto conical member 27 is positioned,and adapted to turn, around the member 19 and is provided with openings28 which correspond with the openings 20. It is to be noted (see Fig. 1)that the openings 20 and 28 in the frustoconical members 19 and 27 areset at an angle .to the radii of those members in order that the airwhich is admitted tangentially into the burner casing may pass into thefuel stream without material resistance and without losing its swirlingmotion. A ring 29 is positioned, and adapted to turn, around the flange22 adjacent the shoulder 26 and has openings 27 corresponding with theopenings 25 in the shoulder. Aperture'd lugs 30 and 31 are provided onthe members 27 and 29 respectively for attachment of some suitablecontrols, as the rods 32, to the outside of the burner-casing. The ring29 is retained adjacent the shoulder 26 by the collar 33 bolted ontotheseat 23 with the flange 22,

the member 27 being held in its socket 34 in the ring 21 by the ring 29.

Referring now to the modification shown in Figures 3, 5 and 6, theburner nozzle-10 is the same as that shown in Figure 1. It is supportedin this instance, however, by a number of brackets 36 supported on amember, 37 embedded in the furnace wall. A ring 35, bolted between thetwo parts 11 and 12 of the burner nozzle 10, is secured to the brackets36 by the bolts 38 thus forming a. rigid support for the nozzle.

Air admission is provided through a radial set of segmental like vanes39 which are pivot ed at their inner ends, in'the enlarged portion 40 ofthe nozzle member ll near the delivery. end thereof, and at their outerends, at one side, in the supporting member 37.

A flanged ring 41 having recesses 42 in its flange serves to space andsupport the pivot pins 43 at the outer ends of the vanes 39. Near theswinging edge of each vane 39 is provided a pair of apertured lugs 44carryvanes'39 have been set for a particular operating condition.

It is to be noted that the burner shown in Figure 1 has an enclosedcasing and is particularly adapted for use. in forced draft furnaces,whereas, the burner of Figure 3 is particularly adapted for use infurnaces where the natural draft is depended on to draw the air into thecombustion chamber.

r In operation, coal is admitted through the supply connection 16 withsubstantially no more air than is necessary for carrying purposes. Thelocation of the inlet into the nozzle member 12 and the shape of saidmem'ber turns the coal away from the inlet and thus reduces eddycurrents and unnecessarily high air pressures in this vicinity.- As aresult of the angle of admission the coal is given a swirling motion andits velocity increases, as

it swirls toward the delivery opening 24, to. I

about twice the admission velocity. The re duced nose portion of thedelivery end of the nozzle delivers the coal into the chamber in 'astream, of swirling conical configuration,

Air is admitted into the of the burner of Figure 1) and through thevanes 39 (in the burner of Figure 3), which may be more or less closedaccordingto the particular rate of firing obtaining, and it is to I 7section but diminishing toward each end, a fuel inlet, thereto disposedat one end thereof substantially tangentially thereto, together with adelivery opening at the other end.

In testimony whereof I have hereunto signed my name.

' OTTO DE LORENZI.

fuel stream 7 through the openings 20 and 25 (in the case be noted thatair is admitted in both forms with a swirling motion opposite to that ofthe fuel stream. This results in thorough admixture offuel and airalmost before they enter the combustion space proper, and results in ashort and intensely hot flame.

In operating the burner of Figure 1 at very low rates of firing theopenings 20 may be closed entirely and all the air may be admittedthrough the openings 25.

I claim: 7

1. A burner for pulverized fuel comprising a nozzle diminishing in crosssection toward both ends; means for admitting fuel tangentiallythereinto; and a fuel delivery opening in the other end of said nozzle.V

3. A burner nozzle for pulverized fuel burners being substantiallycircular in cross

